使用SQL语句将学生表S中年龄(AGE)大于30岁的记录删除,正确的命令是A)DELETE FOR AGE>30
使用SQL语句将学生表S中年龄(AGE)大于30岁的记录删除,正确的命令是A)DELETE FOR AGE>30 B)DELETE FROM S WHERE AGE>30C)DELETE S FOR AGE>30 D)DELETE S WHERE AGE>30
使用SQL语句将学生表S中年龄(AGE)大于30岁的记录删除,正确的命令是A)DELETE FOR AGE>30 B)DELETE FROM S WHERE AGE>30C)DELETE S FOR AGE>30 D)DELETE S WHERE AGE>30
使用SQL语句将学生表S中年龄(AGE)大于30岁的记录删除,正确的命令是______。
A.DELETE FOR AGE>30
B.DELETE FROM S WHERE AGE>30
C.DELETE S FOR AGE>30
D.DELETE S WHERE AGE>30
A.DELETEFORAGE30
B.DELETEFROMSWHEREAGE30
C.DELETESFORAGE30
D.DELETESWHEREAGE30
(28)使用SQL语句向学生表S(SNO,SN,AGE;SEX)中添加一条新记录,学号(SNO),姓名(SN),性别(SEX),年龄(AGE)字段的值分别为0401、王芳、女、18,正确命令是A)APPEND INTO S(SNO,SN, SEX, AGE) VALUES(’0401’,’王芳’,’女’,18)B)APPEND S VALUES(’0401’,’王芳’,’18’,’女’)C)INSERT INTO S(SNO,SN, SEX, AGE) VALUES(’0401’,’王芳’,’女’,18)D)INSERT S VALUES(’0401’,’王芳’,’18’,女,)
A.APPEND INTO S (SNO,SN,SEX,AGE)VALUES('0401','王芳','女',18)
B.APPEND S VALUES('0401','王芳',18,'女')
C.INSERT INTO S(SNO,SN,SEX,AGE)VALUES('0401','王芳','女',18)
D.INSERT S VALUES('0401','王芳',18,'女')
A. DELETE Age from S
B. ALTER TABLE S DROP Age
C. UPDATE S Age
D. ALTER TABLE S ‘Age’
A.APPEND INTO S(SNO,SN,SXE,AGE) valueS("0401","王芳","女",18)
B.APPEND S valueS("0401","王芳","女",18)
C.INSERT INTO S(SNO,SN,SEX,AGE)valueS("0401","王芳","女",18)
D.INSERT S valueS("0401","王芳",18,"女")
A. DELETE Age from S
B. ALTER TABLE S DROP Age
C. UPDATE S Age
D. ALTER TABLE S ‘Age’
A.APPEND INTO S (SNO,SN,SEX,AGE) VALUES (’0401’,’王芳’,’女’,18)
B.APPEND S VALUES (’0401’,’王芳’ ,18,’女’)
C.INSERT INTO S (SNO,SN,SEX,AGE) VALUES (’0401’,’王芳’,’女’,18)
D.INSERT S VALUES (’0401’,’王芳’,18,’女’)
SQL的DDL主要是定义(20)。若有:
学生关系模式S(Sno,Sname,Age,Sex),
课程关系模式C(Cno,Cname,Teacher)以及
成绩关系模式SC(Sno,Cno,Grade),其中S的属性分别表示学生的学号、姓名、年龄、性别,C的属性分别表示课程号、课程名、任课教师姓名,SC的属性分别表示学号、课程号、成绩。
若要在表S中增加一个“家庭住址”(Address)属性,应使用语句(21)Address VARCHAR(30);若要在表S中删除Age属性,应使用语句:(22);已知某课程的课程号为‘C1’,若要输出该课程的平均成绩,应使用语句:SELECT(23)WHERE Cno=‘C1’;若要删除表S、C和 SC,应使用(24)语句。
A.基本表、视图和索引
B.实体、联系和属性
C.字段、数据类型和长度
D.元组和属性
为了保护您的账号安全,请在“简答题”公众号进行验证,点击“官网服务”-“账号验证”后输入验证码“”完成验证,验证成功后方可继续查看答案!